Khan told Dawn, a Pakistani newspaper, he was kidnapped by Pakistan's Tehreek-i-Taliban and he was not tortured while in their custody. He told the newspaper he spent most of his time in captivity reading and praying, and that he was kept in the Waziristan tribal region.

Khan was abducted in 2010 as he was going to work.

Pakistani officials said security forces have been trying to locate Khan since his abduction.

Pakistani troops are engaged in a counter-insurgency operation in North Waziristan, described by some as one of the biggest militant sanctuaries in the region.

Authorities say the offensive launched in June has killed more than 600 militants. The army has lost around 40 soldiers.